short-term, and plate tectonics and mountain building in the long-term.
Chapter 3, The Global Environment and Its Evolution, is concerned with the crust and its interaction with the fluid envelopes, which is driven by solar energy. Past environmental changes and their effects on life can be determined from the study of sedimentary rocks, which contain the record of ancient environments, including information about the composition of the atmosphere and oceans through time. Studies of continental, oceanic, and atmospheric processes have been revitalized by the integration of this compositional information with interpretations of plate tectonic movement and the resulting changes in distribution of continents and ocean basins. The record of rocks and fossils also documents evolution and extinction and provides an intellectual framework for understanding humanity's place in nature.
Chapter 4, Resources of the Solid-Earth, includes environmental concerns related to resource extraction and use. Groundwater, and the flow and reaction of fluids within the crust, is a pervasive theme associated with most geological resources. The report therefore considers water as well as the traditional earth resources of minerals and fossil fuels.
Chapter 5, Hazards, Land Use, and Environmental Change, addresses the geological problems facing humankind and involves research throughout most of the matrix. Topics include hazards caused by earthquakes, landslides, and volcanic eruptions; environmental changes associated with urban growth, engineering, and agricultural practices; and some modern consequences of the long-term global change reviewed in scientific terms in Chapter 3.
Chapter 6, Ensuring Excellence and the National Well-Being, reviews topics such as education, demographics, instruments and facilities, the revolution in data gathering and handling, and international collaboration.
Chapter 7, Research Priorities and Recommendations, tackles the problem of determining science priorities for the whole array of research activities covered in Chapters 2 through 6 and the sources of federal funding for solid-earth science research. The top-priority and high-priority research selections and the facilities required for their implementation are outlined.
There are two informative short-cut paths between Chapters 1 and 7, highlighted for easy identification. Essays at the beginnings of Chapters 2 through 6 provide the sense of the science in each chapter. At the end of each chapter, the most promising research opportunities are summarized in research frameworks without background detail (these are also collected into a single table in Chapter 7).